Multiple condenser transformer unit



Oct. 30, 1934. c Q COOPER ET AL 1,979,190

MULTIPLE CONDENSER TRANSFORMER UNIT Filed May 9, 1929 5 Sheets-Sheet l f 5*-..1..- /P j Z9 5 25 45 gwwnto'cs L. 0. Cooper, 11 LJoknso/n.

Oct. 30, Q Q COOPER ET AL 1,979,190

MULTIPLE CONDENSER TRANSFORMER UNIT Filed May 9, 1929 3 Sheets-Sheet 2 mmgm n 0. 0; aa zz L.i0kman.

dhtomwq 1934- c. o. COOPER El AL MULTIPLE CONDENSER TRANSFORMER UNIT Filed May 9, 1929 5 Sheets-Sheet 3 I I I I g'nwnt 01; C. 0. Caa aez; E L. dimsafl Patented Oct. 30, 1934 UNITED STATES NT FFEQE Charles 0. Cooper and Roy L. Johnson, Saluda, N. 0.

Application May 9, 1929, Serial No. 361,700

Claims.

This invention relates to radio apparatus and particularly to a multiple variable condenser transformer unit.

The general objects are to provide a construc- 5 tion which secures additional selectivity, improves tonal qualities and also sensitiveness in any broadcast receiver irrespective of the particular circuit into which it may be built.

An additional object is to provide a construction in which the switch is operated automatically in conjunction with two or more variable condensers in a unit with two or more radio frequency transformers, each unit to be controlled as at present through the use of separate dials or tuned in unison with one dial, each dial making three hundred and sixty degrees to cover the complete range of a set.

It is also aimed to provide a construction which may be used in connection with the broadcasting of sound and sight for television, when the sound and sight are sent on separate waves.

It is further aimed to provide a construction in which the contacts and electrical parts all have effective engagement and particularly avoid pigtails or other connections of the same general character which frequently develop trouble.

Various additional objects and advantages will become apparent from a consideration of the description following taken in connection with accompanying drawings illustrating an operative embodiment.

In said drawings:--

Figure 1 is a plan view of the unit, certain of the electrical connections being diagrammatically 35. suggested,

Figure 2 is a vertical sectional view taken on the line 2-2 of Figure 1,

Figure 3 is a rear View of the unit,

Figure 4 is a sectional view taken on the line 4 4 of Figure 1,

Figure 5 is a rear elevation of the switch-controlling cam,

Figure 6 is a sectional view taken on the line 6-6 of Figure 4,

Figure 7 is a sectional view taken on the line 77 of Figure 5,

Figure 8 is a sectional view taken on the line 8-8 of Figure 5,

Figure 9 is a sectional view taken on the line Figure 12 is a sectional view taken on the line 12-12 of Figure 1, and

Figure 13 is a view in electrical diagram showing the invention embodied in a radio circuit.

Referring specifically to the drawings, the unit go in a general Way is best shown in Figures 1 and 2. Such unit employs certain parts rigidly connected together in order to support and mount the movable parts. To this end, substantially triangular or other shaped plates are provided at l0, l1, 12 and 13, each being of suitable insulating material. Said plates are suitably fastened rigidly together by means of rods or bolts 14 on which suitable spacers 15 are strung, as well as additional parts hereinafter referred to, properly spacing and rig- 7 idly holding the plates apart. A bolt 16 joins the plates 11 and 12 centrally and at their top while a bolt 17 joins the plates 10 and 11 centrally and at the bottom.

Journaled in the plates 10, ll, 12 and 13 so that it may be turned manually a complete revolution, is a spindle or shaft 18, preferably carrying an operating knob 19 and a suitably calibrated dial 20 rigid therewith for operation in connection with a fixed pointer or the like (not shown). A spring device 21 applies outward longitudinal pressure on the shaft 18. Such shaft is screw threaded throughout and is engaged by nuts 22 at appropriate locations engaging one or more of the plates so as to position the shaft. The open- 5 ings in the said plates through which the shaft 18 passes are of such a size that the screw threads of the shaft do not affect the application and removal of the shaft.

Between the plates 10 and 11 a variable con- 9 denser generally designated A is provided and between the plates 11 and 12 a variable condenser B is disposed. Such condensers A and B are operable from the same shaft 18. Operation of the condensers A and B respectively tune radio frequency transformers C and D, respectively, the condenser A through operation of shaft 18 one hundred and eighty degrees serving to tune the transformer C to work wave lengths or frequencies from fifteen hundred kilocycles to one thousand kilocycles while the condenser E works wave lengths from one thousand kilocycles to 550 kilocycles. In lieu of the two condensers A and B, more may be used as will be obvious. 1

Referring specifically to the transformers C and D, each comprises a tube or spool 23 of insulation, a primary winding 24 thereon and a secondary winding 25 thereon. Spools 23 are carried by the bolts 14, the bolts passing thereno through and nuts 26 serving to fasten them against accidental displacement.

Reverting to the variable condenser A its stator plate is shown at 27 as secured to spools 28 and '29. The bolts 17 secure the spools 28 in place while the spools 29 are threaded on the bolts 14 and insulated from the latter. The movable plates or blades coact with the stator plate 27 are shown at 30 suitably carried by a sleeve 31 of insulation fastened to the shaft 18, and which plates are spaced by conductor rings 32. A conductor 33 connects one of the sleeves 29 with the transformer C and a conductor 34 connects said transformer with a contact 35 which is constantly in wiping engagement with one of the disks 32. As a result, when the transformer C is out into the radio circuit, it will coact with the condenser A in the usual manner.

Relative to the condenser B its construction is quite similar to that of the condenser A, both the stator blades and the movable blades beingdisposed one hundred and eighty degrees from the position occupied by the corresponding blades of condenser A. For instance, bolt 16 mounts a sleeve 36 from which the stator blade 37 extends, such blade also being mounted by sleeves 38 which are disposed on and insulated from the bolts 14. The coacting movable blades are designated 39, and with conducting rings it, properly spacing them, are mounted by an insulating sleeve 41, rigidly secured on the shaft 18 in any suitable manner, one of the rings 40 having a contact 42 fastened to plate 11, constantly wiping the same. The electric circuit between the condenser E and transformer D is produced through a conductor 43 which leads to the contact 42 and transformer D and aconductor 44 which leads from the transformer D to one of the sleeves 38.

As previously intimated, only one transformer C or D is in the electric circuit of the radio set at a time, that is when condenser Ais tuning, transformer C is in circuit but the tuning is transferred to the condenser E, which occurs automatically through the turning of the shaft 18, the transformer C is cut out of the set and the transformer D is thrown into the circuit, thus being in circuit simultaneously with the condenser B. This action or automatic control is performed by a novel switch mechanism generally designated E, which is actuated by the shaft 18.

Referring specifically to the switch mechanism E, similar resilient contacts 50 are fastened in any desired manner as by means of bolts 50 to the plate 12 and engageable with the contacts 50 are contacts 51 which are fastened in any suitable manner as by bolts 52. Such contacts 51' are resilient and urged at their free ends toward the contacts 50 by means of expansive springs 52 as best shown in Figure 6, retained in place by a hook end 53 of the contacts and a recess 54 in the plate 13;

Rigidly fastened on shaft. 18 midway of the plates 12 and 13, is a contact-control or switchcontrol disk 55 made of suitable insulating ma- ,terial. Such disk is provided with an annular groove 56 which extends for one hundred and eighty degrees completely through the disk as at 5'7 and for the remaining one hundred and eighty degrees extends but partly through the disk 55,

in order to provide a barrier wall 58, the.'terminals of which are gradually shaped off to points as best seen in Figure 6. As a result of this construction, one of the contacts 51 is in engagement with itscoacting contact 50 while the other contact 51 cannot engage its coacting contact 50 because the barrier 58 is interposed. In this way, but one of the transformers C or D can be cut into the circuit at a time.

Conductors 59 lead from the transformers C and D and are both connected with the positive feed wire from the radio circuit. A conductor 60 is connected to the plate of the tube in connection with which the unit is used, such conductor having branches 61 secured to the bolts 52 whereby the conductor is common to the contacts 51.

The unit is shown diagrammatically in a radio circuit or hook-up in, Figure 13. Conventional electrical symbols are used and hence it is believed to be unnecessary to specifically describe and trace the various circuits. It may be mentioned however that the three tubes shown as at F, G andH, may represent for example, a detector, a first stage of radio frequency, and a second stage of radio frequency. At each stage of radio frequency, one of the control units constituting the present invention is used.

As a result of the construction described, wit electric current flowing through the radio circuit of Figure 13, with contacts 51 corresponding to condenser A, extending through the slot 5'7 and engaging its coacting contact 50, turning of shaft 18 will cause the condenser A to tune the transformer C in a range of from fifteen hundred KC to one thousand KC, for example. Through the continued turning of the shaft 18 to an extent where tuning would be in'wave lengths or frequencies from one thousand KC to five hundred and fifty KC, the transformerD would be automatically brought into electric circuit with the condenser E while the transformer C and condenser Awill be .cut out of the electric circuit because turning of the control element 55 will cause successively, the barrier 58to engage each previously mentioned contact 51, movingit, out

of engagement with its coacting contact 50, and permitting engagement of the other pair ofcompanion contacts 50 and 51.

.Various changes may be resorted to provided they fall-within the spirit and scope of the ini vention.

We claim as our invention:-

1. A tuning device comprising two tuning units, 7

each unit being for a wave length range different from the-other unit and comprising an opera-.

and then cut out the last mentioned unit and cut-= in the other unit in succession so that a single transformerand condenser will be in-- circuit at the same time.

2. A tuning device comprising two tuning units,

each unit being for a wave length range different condenser having stator plates and movable plates, a shaft carrying the movable plate of both units and rotatable in a single direction, and elec-' the circuit means including a switch mechanism fromthe other unit andcomprisingan operaitively connected condenser and transformer, each controlled by said single movement of the shaft to close an electric circuit through one unit only and then out out the last mentioned unit and out in the other unit in succession so that asingle transformer and condenser willbe circuit at '7 the same time. i

3. A tuning device comprising twotuningunits,

each unit being for a wave length range different from the other unit and comprising an operatively connected condenser and transformer, each condenser having stator plates and movable plates, a shaft carrying the movable plate or both units and rotatable in a single direction, and electric circuit means including a switch mechanism controlled by said single movement of the shaft to close an electric circuit through one unit only and then cut out the last mentioned unit and cut in the other unit in succession so that a single transformer and condenser will be in circuit at the same time, said condensers being arranged in spaced relation lengthwise of the shaft and in different substantially non-intersecting zones about the axis of the shaft, mounting plates for the shaft, parts of the switch and part of the condensers, fastenings for the mounting plates, and each condenser being carried by a different fastening.

4. A tuning device comprising two tuning units, each unit being for a wave length range different from the other unit and comprising an operatively connected condenser and transformer, each condenser having stator plates and movable plates, a shaft carrying the movable plate of both units and rotatable in a single direction, and electric circuit means including a switch mechanism controlled by said single movement of the shaft to close an electric circuit through one unit only and then cut out the last mentioned unit and cut in the other unit in succession so that a single transformer and condenser will be in circuit at the same time, said switch member being disposed between a pair of supporting plates, said switch member being supported by said pair of supporting plates and by said shaft.

5. A tuning device comprising two tuning units, each unit being for a wave length range different from the other unit and comprising an operatively connected condenser and transformer, each condenser having stator plates and movable plates, a shaft carrying the movable plate of both units and rotatable in a single direction, and electric circuit means including a switch mechanism controlled by said single movement of the shaft to close an electric circuit through one unit only and then cut out the last mentioned unit and cut in the other unit in succession so that a single transformer and condenser will be in circuit at the same time, supporting plates for the units, fastening elements securing the units and supporting plates together, said switch mechanism including contacts on one of the plates electrically connected to the transformers, contacts on another plate engageable with the first mentioned contacts, and a control element on the shaft having a perforate and an imperforate portion controlling the engagement of said contacts.

CHARLES O. COOPER. ROY L. JOHNSON. 

